


Fatal Sin & Mortal Flaw

by ValkyrieofArdyn



Series: King and Queen of Darkness [1]
Category: Final Fantasy XV
Genre: Anal Play, F/M, NSFW, Smut, Tentacles, WTF, but want, demon ardyn, demon tentacles, gagging, kinks i have no experience with, minor blood play
Language: English
Status: Completed
Published: 2017-07-09
Updated: 2017-07-09
Packaged: 2018-11-29 18:58:45
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 4,173
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/11447040
Author URL: https://archiveofourown.org/users/ValkyrieofArdyn/pseuds/ValkyrieofArdyn
Summary: The reader finds themselves discarded by Ardyn after they discover is demon form. Not willing to be let go of so easily they pursue him, finding him residing in Insomnia. Ardyn lays them open with his complete demon form.





	Fatal Sin & Mortal Flaw

**Author's Note:**

> So I discovered I liked the thought of Ardyn playing around with tentacles. Tentai is a totally new kink for me (as is blood and anal), but my trash Lord demanded this to be written. It is fluffy. I tried to dig up my inner mean person, but my muse just couldn't work with an abusive mean demon Ardyn (the popular expression of him). Therefore, this little demon Ardyn is much more tender than others. 
> 
> Song Inspiration: Warrior by Beth Crowley

   Walking up the Crown City citadel steps you aren't sure what your plan was once you found Ardyn. All you know is that you want answers. Filled to the brim with anger and hurt that he had cast you away without giving you a chance to stay at his side.

     In the three years dating Ardyn, you had come to understand that there was something more to him. His eloquent and over the top mannerisms veiling a dark secret dwelling within him. It was the shadows and secrecy surrounding him that initially drew you to him. Ever trying to solve the hidden reason for his occasional pained and broken look he would display on the darkest of nights, while held in your arms.  It was only on the eve of Leviathan's destruction of Altissia that you saw what he had been hiding. That was also the same night he cast you away.

      When Ardyn came home that night, you had not been expecting to see him. He had kept limited contact with you while on “political” business in Lucis after the fall of Insomnia. With the events in Altissia, you had figured he would be out of touch for another long span of time. So when the brush of his stubble on your chin awoke you, a smile had graced your lips as you hummed in pleasure.  Ardyn had been quick in letting you know what his intentions were by pressing his naked frame into your body. His hard length poking into your panties, seeking entrance.

      Things had escalated quickly into a passionate session of lovemaking. Ardyn had seemed like a  different man though. Treating your body harsher than usual, leaving bruises and bite marks you would find the next morning. It was in the throes of your orgasm, followed closely by his own, that you finally got a glimpse of the dark secret Ardyn kept. His handsome face had become that of a demon. The black substance leaking from his eyes and mouth, thick and shiny. His skin turned an almost translucent pallid color contrasting eerily with his yellow eyes surrounded by the black sclera.

     The sight of him had so startled you, that you had let out a gasp of shock. Squeaking out his name in question. Your body had been a mess of emotions. Fear battling with the last waves of ecstasy from your release. It must have shown on your face for Ardyn had given you a sarcastic smile, causing more black ooze to escape his lips. “Ah, my love, you finally got what you wanted. You now know my mysterious secret. Alas, as expected it seems like it is more than you can handle.”

   You hadn't moved as he leaned down to your face, your mind still in disarray and trying to comprehend what you were seeing. Ardyn had placed a chaste kiss on your mouth as he exited your core. Leaving a wetness covering your lips, you assumed had been the black substance coating his. A swift onset of fatigue had overtaken you then, and as your consciousness ebbed away, you heard him murmur, “You are my fatal sin (Y/N), but you are not suited to the darkness.”

     When your eyes opened next, you had found yourself in an unknown room. The events of the night foggy at first, adding to the confusion you felt. Upon rising, you had taken a look out of a window and recognized the town of Lestallum sprawling out before you. Completely disoriented, you picked up a neatly folded piece paper you noticed lying on the desk beside the bed. Upon unfolding it, you had immediately recognized the perfect cursive handwriting that belonged to Ardyn.

    _My dear (Y/N), The time has come for me to take my leave. As a farewell, I have deposited you back in your hometown, Lestallum. Your hotel room has been paid for the next month as recompense for any inconvenience. Sincerely, Ardyn_

 

     You had read the letter several times, trying to make sense of it. That after three years of time and experiences shared together, he would cast you away with three sentences. The audacity of it had your anger overwhelming the sorrow you had initially felt upon reading the letter. Then the last words he spoke to you, came back to your awareness, along with the visage of him you had witnessed.  Your anger then turned inward at how you had reacted to seeing his secret for the first time.

  When thinking of his monstrous appearance, what stood out in your memory the most was his eyes. Eyes brimming with black ooze, amber irises eerie as can be, but the despair in them was all too human. Ardyn in his true form, rejected by you. Remembering your instinctual reaction of shocked terror at seeing him, you knew it was the cause of his remorse and reason for pushing you out of his life.

  “You are not suited to the darkness,” that last statement of his has haunted you since waking up in Lestallum. You didn’t feel relief at being granted release from his “darkness,” even though you felt like you logically should. Instead, you felt anger at yourself for not embracing Ardyn’s true self and frustration at Ardyn for not giving more than a moment's chance. Determined not to let those be the last words spoken to you, you had taken it upon yourself to find him again and demand answers. He was your mortal flaw, making you yearn to be part of his darkness, his world, and you love him for it.

     When you had attempted to make your way back to Niflheim, quickly you realized that Ardyn had thoroughly stranded you in Lucis, leaving you without any of your Niflheim ID cards or phone. Thus, the empires boundary road and boat blockades kept you unable to travel outside of Lucis. For a month you had toiled away at trying to find a way back to him, and then perpetual darkness descended. Even though the empire was rumored to be fallen, the hordes of demons roaming the night kept you from traversing to Niflheim. Despair had settled in when you thought that you would never see Ardyn again. Leaving so many things left unsaid, unable to convince him of your love, no matter what he was.

       Then a month after darkness fell you heard the rumor that a man had taken up residence in the Crown City Citadel, along with the holy Crystal and hoards of demons. When hearing the rumor, your gut told you that it was Ardyn. You didn’t understand his connection to the Crystal, but the demon connection was undeniably him. You had realized after a time that the black ichor you had seen was the same as those infected with the Starscourge. 

      The trek to Insomnia began as soon as you suspected Ardyn was there. Since you aren’t a warrior, only working as Ardyn’s secretary, it had taken nearly over a month to get to the Citadel steps. Stealthily avoided demons and getting assistance from others when able. Now finally at the entrance to where Ardyn resided, the frustration at the situation was fresh, and you were resolute to stay with him no matter what. _Even if that means becoming part of his "darkness," but first he needs to answer for his actions._  Pushing away the fatigue from your laborious travels, you pull open the heavy Citadel doors.

    As you enter the Citadel, you begin to wonder where to find Ardyn in the large building, when suddenly he is before you as if out of thin air. Appearing as healthy and handsome as he ever had, no hint of his demonic appearance. Ardyn gives you a wane smile as he slowly approaches you.

   “I expected, you to put two and two together after what you saw (Y/N), but I did not think you would come back, my dear.” He was now only a foot away, and his familiar luscious scent envelops you. Triggering nostalgic memories of his soft caresses to flit through your mind. Ignoring the draw to embrace him, you focus on the anger and hurt of being left behind before answering.

  “Naturally Ardyn,” You drawled out, sarcasm thick in your voice, “I was uprooted from my home and abandoned in a hotel. With a sorry excuse for a farewell.” An unwanted quiver entered your voice as your pent-up anger was finally being expressed. “Why did you cast me away so quickly?! Why didn’t you give me a chance to accept you?! You had no right to make that decision on your own!” you fumed as your chest tightened up from the pain of being discarded. Collecting yourself, you take a deep breath, before continuing. Willing your stomach to stop it's useless flip-flopping. “What was I to do Ardyn? Just forget what we had together? I don’t think so. I don’t know what I saw that night...but I want to know. I love all of you and want to know...all of you.” To your displeasure, your voice sounded weak and pleading. The anger fizzling out, replaced by the need to be in his arms. To live in his world once more.

   Ardyn throughout your emotional rant had kept a neutral face, eyes never leaving yours. Once you finished though his face looked at you patronizingly, “(Y/N) you do not know what you seek. With the darkness ever present, I am not capable of holding the daemon within at bay. Are you truly willing to live in the depths of darkness? Undoubtedly becoming tainted yourself. Will you sacrifice all to be with me? The darkness of the legends.” Even though Ardyn's body language was dismissive and his tone harsh, you saw in his eyes which answer he wanted.

  “Ardyn, you ARE my everything, which includes all that you are. Do not push me away without giving me a chance to decide for myself.” Confidently you close the gap between you two, sliding your arms around his strong back and resting your head on his chest. Feeling the rise and fall of his chest, the knot in your chest formed months ago loosens, and you whisper, “Please Ardyn let me stay. The darkness does not scare me as long as you are there.”

   After a couple of seconds hesitation, Ardyn grips your shoulders while kissing the top of your head. His breath hot on your scalp as he says, “If that is your desire, I will show you who you have truly lain with these past years.” A moment later he lifts you up into his arms and your surroundings become a blur. The inverted and twisting feeling causing your stomach to bottom out.

   When the world stops spinning and your stomach rights itself, you find yourself in a lavish bedroom. One fit for a King. Clutching Ardyn’s neck still dizzy from whatever he just did, you turn your face up to inquire about his method of travel, but your lips become occupied by his.

    Ardyn descends upon you hungrily, lips making harsh movements against yours. The ferocity of his kiss takes your breath away as your lust for him barraged your senses. You responded in kind with urgency, delving your tongue into his mouth, seeking the taste of him. Your slick tongues explored each other's mouths, becoming reacquainted again. Teeth hitting against each other in your passion, halting further exploration.

   Frustrated, you take his bottom and bite down hard on it. Ardyn lets out a low moan as you suck on his now tender lower lip, the taste of iron on your tongue. You had not meant to break his flesh, but the frenzied look in Ardyn’s eyes showed that he wasn't displeased. “I don’t want you to hold back Ardyn. I can take it," you said breathlessly, gaze sure in its steadiness. 

   At that Ardyn had smiled, and while leaving a trail of kisses down your sensitive neck, murmured, “We shall see.”  Your body shivered, and goose bumps rose on your skin from the mixture of arousal and fear at his subtle warning.

    Ardyn then walked over to the bed, setting you down beside it and began undressing you. The light grazes his fingers trailed on your skin as he pulled off your clothes, felt like traces of fire going down into your core.  Once you were down to only your panties, you began undressing him, making quick work of it but Ardyn still had enough time to fondle your breasts. Pinching and pulling on your nipples, causing cries of pleasure to escape as you tried to stay focused on your task. 

   When Ardyn is finally naked, cock hard and free, your panties are soaked through. Reaching down, Ardyn caresses your sex through the fabric, the pressure causing you to grip his arms in pleasure, a mewl rising from your throat as you close your eyes to let the sensations envelop you.

   “Now that we are appropriately ready, let the fun begin.” You open your eyes to look at Ardyn when his usually smooth sultry voice became low and gravely. He was towering over you now in his daemonic form, and you can’t help but feel intimidated by his presence. An instinctual part of you acknowledging that he was indeed a dangerous man, but you found your burning for Ardyn increased with the thrill of the danger. Bright yellow eyes stared into yours, as a pale, dark-veined hand caresses your face, while the other goes underneath your panties and fingers run along your slick folds.

   Your heart beats frantically in your chest from the combination of adrenaline and carnal desire filling you. Legs shaky and unsteady as you were undone by Ardyn's deft fingers rolling over your sensitive nub. Looking into Ardyn's eyes that were beginning to leak black ooze, you mewled, “Take me now Ardyn.”

   The animalistic growl he releases as he picks you up by your ass and thrusts you down onto the bed, makes your endorphins surge with fear and anticipation. You feel a warm wetness pool in between your legs further as the need to have him inside you overwhelms your mind. In a frenzy you crush your lips back onto his, enjoying the new bitter spicy taste on your tongue, that must be from the black substance now coating his mouth. Seeking his relief of built up desire, Ardyn grinds his hardened member into your stomach, his pre-cum wetting your skin.

    Releasing your lips, Ardyn begins sucking and biting down your neck. Hands tangled in your hair pull your head back to gain better access. The sucking and biting are nothing new until he reaches the crook of your neck bites deeply into your meaty flesh. You exclaim in pain and try to pull away, but he holds you fast. The pain is quickly forgotten as he begins to suck and lap at the wound. The injured flesh more capable of appreciating Ardyn's ministrations as he soothed the area with his tongue. With each suck of his mouth and swirl of his tongue, your clit throbbed in need to feel those sensations long it's sensitive nerves.  

   As if bidden, the sudden touch on your clit causes you to release a whimper of desperation, squirming as your nerves fire off. Enjoying the sensation of your bundle of nerves being rubbed deliciously, it takes a moment to realize that both of Ardyn’s hands are still occupied, tangled in your hair. 

    When Ardyn hears your confused exclamation, he released the hold on your head and sits up, allowing you to look down at what was touching you. To your surprise you see a long round black tentacle deftly circling your clit, feeling very similar to a tongue's movements. Looking at it you realize that the wetness between your legs was no longer just your own, the tentacle now added its own slickness. While mesmerized with the limb fondling your clit, you see another smooth black tentacle appear and begin to probe your entrance, running up and down your wet folds.

    You gasp as it enters you slowly, and look up into the demonic amber eyes staring down at you. “Oh! Ar-Ardyn!,” is all you get out as you arch your back with the exquisite sensation of being filled in a whole new way. The tentacle inside your sex was not as firm has Ardyn’s cock but was much more dextrous and never failed to rub against your rough patch lining your wall, as it was pulled in and out of you at a savage pace. Ardyn lets out a contented hum of pleasure at seeing the enjoyment you were taking from his tentacles, your body writhing beneath him.

     With the ministrations against your clit and g-spot, you found the built up sexual tension coming to a sudden head. Your orgasm is earth-shaking, waves of euphoria flooding your system.  Ardyn lets you ride out your orgasm, continuing to pump in and out of you with a tentacle as he watches you while caressing his length with a hand. “You are absolutely magnificent (Y/N),” Ardyn moaned just as you reach the edge of your high. He then latches his mouth onto one of your breasts, sucking hard. You let out a loud keen as your sensitive nipple is rolled around with his tongue, teeth biting down on it sporadically.

      Wanting to touch him yourself, you begin reaching up towards his head, but your wrists are halted quickly by strong, slick tentacles. “I shall do the touching tonight my love. This is a test of what you can handle from me,” Ardyn growls in a rough voice after releasing your breast with a pop and holding your arms out to the side.  

    You found yourself quickly immobilized by tentacles wrapping themselves around your thighs, curling all the way down to your calves. Even as more tentacles came to circle your breasts and waist you weren’t worried. You felt oddly secure by the tentacles tightly embracing you and sliding along your skin. Looking up at Ardyn, he honestly looked monstrous with a multitude of tentacles coming out from his back, pale skin lined with black veins, and eyes overflowing with black tears. You no longer any fear at his appearance though. Only eagerness for what he had planned, a coil of heat winding up once more between your legs.

     You felt your body begin to reach another climax from the continued tentacle stimulation on your clit, breasts, and sex. As you let out the telltale moans of your arriving release, Ardyn leans down and kisses you deeply, snaking his tongue into your mouth. Your sex suddenly becomes empty as the tentacle exists, but before you can whine in displeasure, it is quickly filled with Ardyn’s well known hard length. He thrusts in hard, going all the way to the hilt. Tongue entwined with his, all you get out is a muffled gasp from the expanse of his hard member rubbing against your walls. As he begins to pump in and out of your roughly, you feel a gentle circling around your ass. 

   The foreign sensation around your other entrance sends a spike of wariness through you, dampening your rising climax. Anal play being something you had never felt the need to try. Brushing off Ardyn in the past when he would mention trying it.  _What a way to introduce it Ardyn when using tentacles on me for the first time as well._ The errant ironic thought made you smile into Ardyn’s kiss. Even though you felt uncertain, you kept it to yourself, wanted to show him your willingness to persevere. 

      The tentacle continued to circle the tight ring of muscle, and you felt it begin to loosen, the slime from the tentacle lubricating the opening. As Ardyn pushed the tentacle slowly into your ass, it caused you to clench up and whimper in pain from the stretching. In response the tentacles surrounding your limbs and torso convulse, tightening their grip.  Soon after the initial stretch and suffering of the tentacle entering your tight ring, the feeling of the slick appendage moving in and out of you became obscenely pleasing. It's diameter widening slowly as the muscles around it relaxed. 

    A sense of fullness filled your abdomen once his tentacle stopped its slow progression, deep within. When Ardyn began pumping his cock and tentacle in time with each other, you cried out his name over and over, your sensories overloaded. You would have squirmed away from the sheer nerve stimulation but his tentacles kept you firmly in place. Which was for the best because there was nowhere else you would rather be.

  Once your sounds become ones of pleasure again, Ardyn releases your lips and looks down at you. Looking into his eyes, you see that they are almost entirely black with is pupils fully dilated. He smiles down at you as he sticks a finger into your mouth. You obediently latched onto it, sucking and swirling your tongue around it greedily, looking up at him, eyes half-lidded from bliss. “That’s a good girl. You are taking all of me so well,” Ardyn purrs as he speeds up the pumping of both cock and tentacle.

    You hadn’t noticed when your clit had stopped being stimulated, but you were aware the moment you felt it being flicked again by a tentacle. With your mouth occupied by two fingers now, you let out a low mewled as the tingling heat around your sex builds up once more, begging for release.

     Moments before you crest, you experience a sense of vertigo as your body is flipped up, and you find yourself riding Ardyn, the climax forgotten once again in your surprise. Without missing a beat Ardyn continues fervently thrusting his tentacle and cock in and out of you, the new angle causing your g-spot to be stimulated once again. With his continued ministrations inside your sex and ass, along with the tentacle rolling over your hypersensitive nub, your climax quickly comes to a head. 

      Ardyn removed his fingers from your mouth and gripped your hips firmly with both hands, fingernails digging into your flesh as he pushes you down onto his cock. The fresh pain from his grasp going straight to your sex. Your walls spasming on Ardyn's member. “That’s it, come for me again (Y/N),” Ardyn groans, loosened his tentacles around your limbs, allowing you to move your hips in time with his thrusts. You feel his cylindrical limbs begin to squeezed and release in time with the gyration of your hips, massaging your muscles pleasantly.

     Looking down at the display underneath you, Ardyn’s half-lidded demon eyes staring at you fervidly, drives you over the edge.  You let out an incoherent scream as your body spasms, and your walls clamp down, drenching Ardyn’s cock in cum. The tentacles are the only thing keeping your body from collapsing, tightening back around you. Ardyn’s thrusting within you increases as he searches for his own release, helping your ride out the last vestiges of your climax.

    When you feel a tentacle curl around your neck, and prod open your mouth, eagerly you take it in. It thrusts down deep into your mouth hitting the back of your throat, causing you to gag. You take a deep breath through your nose and allow your throat to open, as Ardyn begins to thrust it in and out of your mouth. It is in that state of being utterly filled that you feel his tentacles and cock spasm as he releases his seed into you, and you feel it soon drip out of your sex, hot and languid.

     When you feel his cock reduce in size within you, Ardyn removes the tentacles from your mouth and ass. The emptiness that remains causes you to frown down at Ardyn, just barely holding back a whimper. He chuckles at you, his face now a mess of black ooze from your foray together. “Do not look so distraught love. There is plenty of time for many more rounds, but I do believe you are about to pass out.” As his tentacles gently detangled their grip on you and disappeared, Ardyn slid you under the crook of his arm. 

    Curling into the side of his body and laying your head on his chest, you found that you were indeed on the cusp of passing out. Before you did so though, you looked up at the demonic man and placed a kiss on his pallid lips. “If it isn’t obvious yet, I love you Ardyn, all aspects of you. I will stand by your side to the end.”

    As Ardyn brush the sweaty hair off your forehead, his appearance changed back to his human appearance. ‘That is good to hear my dear, for you are now one with me in this darkness. Rest now. I will be here when you awake anew.” Darkness enveloped your consciousness then, but not before you felt a new darkness stirring within you. 

  


End file.
